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<head>
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="./findindex.js"></script>
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<body>
    <script>
        newlist = [1, 2, 3, 4]
        const res = findindex(newlist, item => item > 3)
        console.log(res)
    </script>

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